Today is Saint Patrick's Day, so a little bit of Celtic Twilight, or Irish Mist.

Some years ago - 51 to be precise - I was in a pub where a well-oiled customer was trying to sing a song. It was in Irish and he clearly didn't know the song as he was repeating the same few lines.
After he gave up he turned to me and asked me if I understood what he was singing. I said no, except that it was about somebody called John O'Dwyer. "Seán O'Dwyer", he corrected me. I thought, "OK pal, same thing in my book".
I often wondered after this, who was Seán O'Dwyer, and why was he worth a song. Then, maybe fifteen years later, reading a little book by Frank O'Connor, I came across a poem which he'd translated from the Irish and which he called "Lament for the Woodlands".
The last lines of the first verse were -

"But now the woods are falling
We must go over the water -
Seán O'Dwyer of the valley
Your pleasure is no more."

and there I had it.

So who was this Seán O'Dwyer? No-one of import, as far as I could gather from Frank O'Connor's version. Some dispossessed landowner who, sometime in the 18th century, decided to skulk around his lost lands sponging off his former tenants instead of going "over the water" and into exile. It is clear that in better times his only interest was in his own diversions; hunting, "sporting and playing".
But that's not what the poem is really about, much more is being alluded to; the broken Treaty of Limerick, the flight of the "Wild Geese", the extirpation of the Catholic and Jacobite Irish, the denudation of the land for timber. It is a snapshot, in a few verses, of a time (a nadir?) in Ireland's history, though only, perhaps, from the viewpoint of a particular caste.

Over time I've gathered more information about the original poem/song, which is called in Irish "Seán Ó Duibhir an Ghleanna". One W.J.Fitzpatrick claimed that the author of the poem was a Redemptorist priest named Albert Barry*. The time in which the poem is set seems not to have been established beyond doubt. Some opinions place it in the aftermath of 1691, when English carpetbaggers descended on Ireland seizing the estates of the Jacobite soldiery, in contravention of the guarantees of the Treaty of Limerick. Others place it during the Cromwellian plantations, when "undertakers" and "adventurers"** descended on Ireland bearing titles to the best remaining land in the hands of the "mere Irish".
The latter period is the more likely, as it was then that the forests came to be exploited commercially.

Here is Frank O'Connor's English version of the poem.
Here is the Irish
original with further information and additional verses.
Here is a sung version.

*An 18th century Gael named Albert? Perhaps the Irish Ailbhe was Englished Alby, and some modern commentator thought it short for Albert, though Fitzpatrick would surely have known better.

** "Undertakers" were Englishmen who purchased title to Irish lands. Sometimes they sold the land on to others who were called "adventurers".